If Naruto gets hurt by Sakura, their relationship could become strained. Naruto might be confused and hurt, both physically and emotionally. He might start to avoid Sakura at first.
In many SasuSaku fanfics where Sakura gets hurt, it often leads to Sasuke becoming extremely protective. He might go on a rampage against those who hurt her. For example, in some stories, if Sakura is injured during a battle, Sasuke will use his powerful jutsu to defeat the enemy without mercy. It's a way to show his deep - seated feelings for her that he might not always openly express.
The betrayal could lead to Naruto having trust issues not only with Sakura but also with others in the future. He might become more guarded and less likely to open up to people. For Sakura, if she comes to her senses later, she would have to face the enormity of what she has done. She would have to grovel for Naruto's forgiveness, but it would be a long and difficult road to regain his trust.
One possibility is that it could be a situation where Sakura accidentally hurts Naruto during a training session. Maybe she's trying out a new jutsu and misjudges its power or range, and Naruto ends up getting injured as a result.
In some 'naruto gets hurt fanfic', it could be due to a trap. He might be exploring an unknown area, perhaps an ancient ruin or a hidden lair. There could be traps set by previous occupants or enemies. Naruto, being curious and brave, might trigger one of these traps and get hurt. For instance, a poison - dart trap or a collapsing floor.
One possible scenario could be in a fanfic where Sakura accidentally uses her strength during a training session with Naruto and physically hurts him. Maybe she misjudges her punch or kick.
Naruto could initially be angry. He might think Sakura overreacted. But then, after a moment, he would probably realize his own mistake if there was one. He'd then try to play it off with a joke to ease the tension between them, like he always does in tough situations.
There could be fear as well. Seeing Naruto injured, Sakura might be afraid of losing him. This fear could drive her actions in the fanfiction, whether it's in finding a cure for his injuries or in taking revenge on those who hurt him. It would also add more depth to their relationship as she grapples with these complex emotions.
Perhaps in the fanfiction, there is a plot twist where Sakura has been brainwashed by an antagonist. The antagonist could be using her to get to Naruto, knowing their close relationship. So, she would then be made to attack Naruto without her own will. Or, there could be a prophecy or some sort of pre - determined fate in the fanfiction's plot that causes Sakura to hurt Naruto, even if she doesn't really want to.
It could be due to Sakura's feelings for Sasuke. If she's overly focused on Sasuke and Naruto gets in the way of her plans regarding Sasuke in some way, she might lash out and hurt Naruto without really meaning to cause serious harm.